一，基础
SM4算法输入128bit，输出128bit
构造的hash函数以512bit分组，每个分组分为4个128bit进行4次SM4操作，将每次的输出异或
明文填充长度为64bit，填充方法同MD5，输出消息长度为128bit
详细国密SM4算法参见如下：
二，结构
EHi-1(Mi) xor Mi=Hi
即将Mi加密后的结果与Mi异或得到下一轮使用的密钥
三，代码
1 #include<bits/stdc++.h> 2 using namespace std; 3 4 unsigned long sk[32]; //子密钥or轮密钥 5 vector<unsigned char>X; 6 int Turn;//加密分组数量 7 8 #ifndef GET_ULONG_BE 9 #define GET_ULONG_BE(n,b,i) \ 10 { \ 11 (n) = ( (unsigned long) (b)[(i) ] << 24 ) \ 12 | ( (unsigned long) (b)[(i) + 1] << 16 ) \ 13 | ( (unsigned long) (b)[(i) + 2] << 8 ) \ 14 | ( (unsigned long) (b)[(i) + 3] ); \ 15 } 16 #endif 17 18 #ifndef PUT_ULONG_BE 19 #define PUT_ULONG_BE(n,b,i) \ 20 { \ 21 (b)[(i) ] = (unsigned char) ( (n) >> 24 ); \ 22 (b)[(i) + 1] = (unsigned char) ( (n) >> 16 ); \ 23 (b)[(i) + 2] = (unsigned char) ( (n) >> 8 ); \ 24 (b)[(i) + 3] = (unsigned char) ( (n) ); \ 25 } 26 #endif 27 28 #define SHL(x,n) (((x) & 0xFFFFFFFF) << n) 29 #define ROTL(x,n) (SHL((x),n) | ((x) >> (32 - n))) //循环左移 30 31 #define SWAP(a,b) { unsigned long t = a; a = b; b = t; t = 0; } 32 33 static unsigned char SboxTable[256] = { 34 0xd6,0x90,0xe9,0xfe,0xcc,0xe1,0x3d,0xb7,0x16,0xb6,0x14,0xc2,0x28,0xfb,0x2c,0x05, 35 0x2b,0x67,0x9a,0x76,0x2a,0xbe,0x04,0xc3,0xaa,0x44,0x13,0x26,0x49,0x86,0x06,0x99, 36 0x9c,0x42,0x50,0xf4,0x91,0xef,0x98,0x7a,0x33,0x54,0x0b,0x43,0xed,0xcf,0xac,0x62, 37 0xe4,0xb3,0x1c,0xa9,0xc9,0x08,0xe8,0x95,0x80,0xdf,0x94,0xfa,0x75,0x8f,0x3f,0xa6, 38 0x47,0x07,0xa7,0xfc,0xf3,0x73,0x17,0xba,0x83,0x59,0x3c,0x19,0xe6,0x85,0x4f,0xa8, 39 0x68,0x6b,0x81,0xb2,0x71,0x64,0xda,0x8b,0xf8,0xeb,0x0f,0x4b,0x70,0x56,0x9d,0x35, 40 0x1e,0x24,0x0e,0x5e,0x63,0x58,0xd1,0xa2,0x25,0x22,0x7c,0x3b,0x01,0x21,0x78,0x87, 41 0xd4,0x00,0x46,0x57,0x9f,0xd3,0x27,0x52,0x4c,0x36,0x02,0xe7,0xa0,0xc4,0xc8,0x9e, 42 0xea,0xbf,0x8a,0xd2,0x40,0xc7,0x38,0xb5,0xa3,0xf7,0xf2,0xce,0xf9,0x61,0x15,0xa1, 43 0xe0,0xae,0x5d,0xa4,0x9b,0x34,0x1a,0x55,0xad,0x93,0x32,0x30,0xf5,0x8c,0xb1,0xe3, 44 0x1d,0xf6,0xe2,0x2e,0x82,0x66,0xca,0x60,0xc0,0x29,0x23,0xab,0x0d,0x53,0x4e,0x6f, 45 0xd5,0xdb,0x37,0x45,0xde,0xfd,0x8e,0x2f,0x03,0xff,0x6a,0x72,0x6d,0x6c,0x5b,0x51, 46 0x8d,0x1b,0xaf,0x92,0xbb,0xdd,0xbc,0x7f,0x11,0xd9,0x5c,0x41,0x1f,0x10,0x5a,0xd8, 47 0x0a,0xc1,0x31,0x88,0xa5,0xcd,0x7b,0xbd,0x2d,0x74,0xd0,0x12,0xb8,0xe5,0xb4,0xb0, 48 0x89,0x69,0x97,0x4a,0x0c,0x96,0x77,0x7e,0x65,0xb9,0xf1,0x09,0xc5,0x6e,0xc6,0x84, 49 0x18,0xf0,0x7d,0xec,0x3a,0xdc,0x4d,0x20,0x79,0xee,0x5f,0x3e,0xd7,0xcb,0x39,0x48 50 }; 51 52 static const unsigned long FK[4] = {0xa3b1bac6,0x56aa3350,0x677d9197,0xb27022dc}; 53 54 static const unsigned long CK[32] = 55 { 56 0x00070e15,0x1c232a31,0x383f464d,0x545b6269, 57 0x70777e85,0x8c939aa1,0xa8afb6bd,0xc4cbd2d9, 58 0xe0e7eef5,0xfc030a11,0x181f262d,0x343b4249, 59 0x50575e65,0x6c737a81,0x888f969d,0xa4abb2b9, 60 0xc0c7ced5,0xdce3eaf1,0xf8ff060d,0x141b2229, 61 0x30373e45,0x4c535a61,0x686f767d,0x848b9299, 62 0xa0a7aeb5,0xbcc3cad1,0xd8dfe6ed,0xf4fb0209, 63 0x10171e25,0x2c333a41,0x484f565d,0x646b7279 64 }; 65 66 //文本的填充处理 67 void append(string m) { 68 Turn = (m.size() + 8) / 64 + 1;//8*8=64为填充长度的预留位 69 X.resize(Turn * 64); //Turn为分组数 一组512bit 为64个十六进制 70 int i = 0; 71 for (; i < m.size(); i++) { 72 X[i] = m[i]; 73 } 74 X[i++] = 0x80; 75 while (i < X.size() - 8) { 76 X[i] = 0; 77 i++; 78 } 79 long long int a = m.size() * 8; //明文长度 80 for (i = X.size() - 1; i >= X.size() - 8; i--) { 81 X[i] = a % 256; 82 a /= 256; 83 } 84 } 85 86 //输出填充后的文本 87 void printX() { 88 printf("\n明文填充后为：\n"); 89 for (int i = 0; i < X.size(); i++) { 90 printf("%02x", X[i]); 91 if ((i + 1) % 4 == 0) 92 printf(" "); 93 if ((i + 1) % 16 == 0) 94 printf("\n"); 95 } 96 } 97 98 //S盒转换 99 static unsigned char sm4Sbox(unsigned char inch) 100 { 101 return (unsigned char)(SboxTable[inch]); 102 } 103 104 //T变换 105 static unsigned long sm4Lt(unsigned long ka) 106 { 107 unsigned long bb = 0; 108 unsigned long c = 0; 109 unsigned char a[4]; 110 unsigned char b[4]; 111 PUT_ULONG_BE(ka,a,0) //将8位分在一起 112 b[0] = sm4Sbox(a[0]); 113 b[1] = sm4Sbox(a[1]); 114 b[2] = sm4Sbox(a[2]); 115 b[3] = sm4Sbox(a[3]); 116 GET_ULONG_BE(bb,b,0) //合并为32位 117 c =bb^(ROTL(bb, 2))^(ROTL(bb, 10))^(ROTL(bb, 18))^(ROTL(bb, 24)); //线性变换L 118 return c; 119 } 120 121 //轮函数 122 static unsigned long sm4F(unsigned long x0, unsigned long x1, unsigned long x2, unsigned long x3, unsigned long rk) 123 { 124 return (x0^sm4Lt(x1^x2^x3^rk)); 125 } 126 127 //密钥扩展 变换T*，基本同T 128 static unsigned long sm4CalciRK(unsigned long ka) 129 { 130 unsigned long bb = 0; 131 unsigned long rk = 0; 132 unsigned char a[4]; 133 unsigned char b[4]; 134 PUT_ULONG_BE(ka,a,0) 135 b[0] = sm4Sbox(a[0]); 136 b[1] = sm4Sbox(a[1]); 137 b[2] = sm4Sbox(a[2]); 138 b[3] = sm4Sbox(a[3]); 139 GET_ULONG_BE(bb,b,0) 140 rk = bb^(ROTL(bb, 13))^(ROTL(bb, 23)); 141 return rk; 142 } 143 144 //密钥扩展算法 145 static void sm4_setkey( unsigned long SK[32], unsigned char key[16] ) 146 { 147 unsigned long MK[4]; 148 unsigned long k[36]; 149 unsigned long i = 0; 150 151 GET_ULONG_BE( MK[0], key, 0 ); 152 GET_ULONG_BE( MK[1], key, 4 ); 153 GET_ULONG_BE( MK[2], key, 8 ); 154 GET_ULONG_BE( MK[3], key, 12 ); 155 k[0] = MK[0]^FK[0]; 156 k[1] = MK[1]^FK[1]; 157 k[2] = MK[2]^FK[2]; 158 k[3] = MK[3]^FK[3]; 159 for(; i<32; i++) 160 { 161 k[i+4] = k[i] ^ (sm4CalciRK(k[i+1]^k[i+2]^k[i+3]^CK[i])); 162 SK[i] = k[i+4]; //轮密钥 163 } 164 165 } 166 167 //输出 168 void sm4_print(unsigned char output[16]){ 169 for(int i=0;i<16;i++) printf("%02x", output[i]); 170 printf("\n"); 171 } 172 173 //32轮次轮函数的集成 174 static void sm4_one_round( unsigned long sk[32],unsigned char input[16],unsigned char output[16] ) 175 { 176 unsigned long i = 0; 177 unsigned long ulbuf[36]; 178 179 memset(ulbuf, 0, sizeof(ulbuf)); 180 GET_ULONG_BE( ulbuf[0], input, 0 ) 181 GET_ULONG_BE( ulbuf[1], input, 4 ) 182 GET_ULONG_BE( ulbuf[2], input, 8 ) 183 GET_ULONG_BE( ulbuf[3], input, 12 ) 184 while(i<32) 185 { 186 ulbuf[i+4] = sm4F(ulbuf[i], ulbuf[i+1], ulbuf[i+2], ulbuf[i+3], sk[i]); 187 PUT_ULONG_BE(ulbuf[i+1],output,0); 188 PUT_ULONG_BE(ulbuf[i+2],output,4); 189 PUT_ULONG_BE(ulbuf[i+3],output,8); 190 PUT_ULONG_BE(ulbuf[i+4],output,12); 191 i++; 192 } 193 PUT_ULONG_BE(ulbuf[35],output,0); 194 PUT_ULONG_BE(ulbuf[34],output,4); 195 PUT_ULONG_BE(ulbuf[33],output,8); 196 PUT_ULONG_BE(ulbuf[32],output,12); 197 } 198 199 //设置加密密钥 200 void sm4_setkey_enc(unsigned long Sk[32], unsigned char key[16] ) 201 { 202 sm4_setkey(Sk,key); //计算出32子密钥 203 } 204 205 //进行一轮128bit 206 void sm4_crypt_hash(unsigned long sk[32],unsigned char input[16],unsigned char output[16],unsigned char key[16]) 207 { 208 unsigned char tmp[16]; 209 memcpy(tmp,input,sizeof(unsigned char)*16); //将input赋值给tmp 210 sm4_setkey_enc(sk,key); //得到子密钥 211 sm4_one_round(sk,tmp,output); //对tmp进行SM4 212 for(int i=0;i<16;i++) key[i]=(unsigned char)(output[i]^input[i]); //将加密后的数据与输入异或作为下一轮的密钥 213 } 214 215 int main() 216 { 217 unsigned char key[16] = {0x01,0x23,0x45,0x67,0x89,0xab,0xcd,0xef,0xfe,0xdc,0xba,0x98,0x76,0x54,0x32,0x10}; 218 unsigned char input[16],output[16],Ciph[16]; 219 unsigned long sk[32]; 220 string str; 221 cout<<"请输入明文："; 222 cin>>str; 223 append(str); 224 printX(); 225 for(int j=0;j<16;j++) Ciph[j]=0x00; //初始化为全零 226 for(int i=0;i<Turn*4;i++){ 227 for(int j=0;j<16;j++) input[j]=X[16*i+j]; //从一组中选取128bit 228 sm4_crypt_hash(sk,input,output,key); 229 for(int j=0;j<16;j++) Ciph[j]=Ciph[j]^output[j]; //得到的结果与之前的输出异或 230 } 231 232 cout<<"输出密文为："<<endl; 233 sm4_print(Ciph); 234 235 return 0; 236 }
四，实现截图
